As long as light is incident on a solar module, the solar module produces an output voltage potentially exceeding 1000 V DC with present solar modules with regard to ground potential in idle mode. Thus, in case of a damage, like for example a fire, but also with installation and servicing works, there is the danger of electric shock. To avoid this danger, it is known to provide a solar module with an electric circuitry short-circuiting the solar module, if needed.
The implementation of such an electric circuitry with different solar modules, however, is not trivial. Solar modules have different connection boxes and different connectors at the connection boxes or at lines leading out of the connection boxes and conducting the power current generated by the solar module. There is also no standard with regard to operating such an electric circuitry. All these aspects make it particularly difficult to retrofit an existing solar module with such an electronic circuitry.
From WO 2012/012137 A1, a moisture-resistant connection box for a solar module is known comprising a channel for each of two lines provided with insulations, the channel leading into the interior of the connection box, and a further junction running at an angle of 90° thereto. In the area of the channels, the housing is multi-part and clamped onto the respective line in a sealing way in assembling its parts. The further junction provides a pull relief for the respective line introduced into the channel.
From DE 10 2009 024 516 A1, an electric connection box for electrically connecting a solar module is known. This connection box comprises a housing, two input side connection elements for contacting two lines coming from the solar module, and two output side connection elements for connecting external lines, wherein each one of the input side connection elements is connected to one of the output side connection elements within the housing in an electrically conductive way. The connection box is intended to minimize damage to humans by electric shock in case of a fault in that a safety device is provided within the housing. By means of components of the safety device, an electrically conductive cross connection between the input side connection elements can be established such that the output voltage of the solar module present between the input side connection elements is reduced by the cross connection in an active state of the safety device.
Insulation displacement connectors or terminals are known electric connection devices which cut or pierce the insulation of a line and provide an electric connection to the line. According to EP 1 478 053 B1, insulation displacement terminals allow for a retrofitting of plug connectors to existing lines in low voltage applications, like for example on-board grids of vehicles. EP 2 355 268 A1 discloses insulation-displacement terminals for electrically connecting individual solar modules via lines conducting their power current in parallel to two bus bars.
There still is a need for an apparatus by which, for example, safety and protection devices or diagnostic equipment may be implemented in or particularly retrofitted to solar modules without significant effort.